Re: Phase Plot of Simple Harmonic Motion using Mathematica ??

*To*: mathgroup at smc.vnet.net*Subject*: [mg126506] Re: Phase Plot of Simple Harmonic Motion using Mathematica ??*From*: DC <b.gatessucks at gmail.com>*Date*: Wed, 16 May 2012 04:20:31 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <jot5nd$aok$1@smc.vnet.net>

I would change the definition of solution so it's a simple function of t, then you'd take its derivative/do the plot in the usual way. solution[t_] = NDSolve[{x''[t] + k/m x[t] == 0, x[0] == 5, x'[0] == 0}, x[t], {t, 0, 250}][[1, 1, 2]] ParametricPlot[{solution[t], solution'[t]}, {t, 0, 100}]